Sherlock Holmes was a man who seldom took exercise for exercise’s sake. Few men were capable of greater muscular effort, and he was undoubtedly one of the finest boxers of his weight that I have ever seen; but he looked upon aimless bodily exertion as a waste of energy, and he seldom bestirred himself save when there was some professional object to be served. Then he was absolutely untiring and indefatigable. That he should have kept himself in training under such circumstances is remarkable, but his diet was usually of the sparest, and his habits were simple to the verge of austerity. Save for the occasional use of cocaine, he had no vices, and he only turned to the drug as a protest against the monotony of existence when cases were scanty and the papers uninteresting. (p.547)

“Watson,” said he, “if it should ever strike you that I am getting a little over-confident in my powers, or giving less pains to a case than it deserves, kindly whisper ‘Norbury’ in my ear, and I shall be infinitely obliged to you.” (p.565)

“You have formed a theory, then?” “At least I have got a grip of the essential facts of the case. I shall enumerate them to you, for nothing clears up a case so much as stating it to another person, and I can hardly expect your co-operation if I do not show you the position from which we start.” (p.523)

“Inspector Gregory, to whom the case has been committed, is an extremely competent officer. Were he but gifted with imagination he might rise to great heights in his profession. …. (p.527)

“See the value of imagination,” said Holmes. “It is the one quality which Gregory lacks. We imagined what might have happened, acted upon the supposition, and find ourselves justified. Let us proceed.” (p.535-536)

We all sprang out with the exception of Holmes, who continued to lean back with his eyes fixed upon the sky in front of him, entirely absorbed in his own thoughts. It was only when I touched his arm that he roused himself with a violent start and stepped out of the carriage. “Excuse me,” said he, turning to Colonel Ross, who had looked at him in some surprise. “I was day-dreaming.” There was a gleam in his eyes and a suppressed excitement in his manner which convinced me, used as I was to his ways, that his hand was upon a clue, though I could not imagine where he had found it. (p.531)